From d4c3083c422183abe71cdb6dd97c3ffbdf0c18ff Mon Sep 17 00:00:00 2001
From: Andri Yngvason <andri@yngvason.is>
Date: Sun, 5 Nov 2023 10:29:01 +0000
Subject: [PATCH] server: Remove DNS lookup

DNS lookup is slow and can even fail. Under some circumstances, it will
even block for a significant amount of time until it completes.

The user of this library can do the lookup instead if they wish.
---
 src/server.c | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/src/server.c b/src/server.c
index 0119eb4..6381b4a 100644
--- a/src/server.c
+++ b/src/server.c
@@ -82,6 +82,8 @@ static void on_encode_frame_done(struct encoder*, struct rcbuf*, uint64_t pts);
 static bool client_has_encoding(const struct nvnc_client* client,
 		enum rfb_encodings encoding);
 static void process_fb_update_requests(struct nvnc_client* client);
+static void sockaddr_to_string(char* dst, size_t sz,
+		const struct sockaddr* addr);
 
 #if defined(GIT_VERSION)
 EXPORT const char nvnc_version[] = GIT_VERSION;
@@ -1673,21 +1675,23 @@ static void on_client_event(struct stream* stream, enum stream_event event)
 	client->buffer_index = 0;
 }
 
+// TODO: Remove this when nvnc_client_get_hostname gets renamed.
 static void record_peer_hostname(int fd, struct nvnc_client* client)
 {
 	struct sockaddr_storage storage;
 	struct sockaddr* peer = (struct sockaddr*)&storage;
 	socklen_t peerlen = sizeof(storage);
-	if (getpeername(fd, peer, &peerlen) == 0) {
-		if (peer->sa_family == AF_UNIX) {
-			snprintf(client->hostname, sizeof(client->hostname),
-					"unix domain socket");
-		} else {
-			getnameinfo(peer, peerlen,
-					client->hostname, sizeof(client->hostname),
-					NULL, 0, // no need for port
-					0);
-		}
+	if (getpeername(fd, peer, &peerlen) < 0) {
+		nvnc_log(NVNC_LOG_WARNING, "Failed to get address for client: %m");
+		return;
+	}
+
+	if (peer->sa_family == AF_UNIX) {
+		snprintf(client->hostname, sizeof(client->hostname),
+				"unix domain socket");
+	} else {
+		sockaddr_to_string(client->hostname, sizeof(client->hostname),
+				peer);
 	}
 }
 
@@ -1774,6 +1778,11 @@ static void sockaddr_to_string(char* dst, size_t sz, const struct sockaddr* addr
 	case AF_INET6:
 		inet_ntop(addr->sa_family, &sa_in6->sin6_addr, dst, sz);
 		break;
+	default:
+		nvnc_log(NVNC_LOG_DEBUG,
+				"Don't know how to convert sa_family %d to string",
+				addr->sa_family);
+		break;
 	}
 }
 
@@ -2265,6 +2274,8 @@ struct nvnc* nvnc_client_get_server(const struct nvnc_client* client)
 	return client->server;
 }
 
+// TODO: This function should be renamed to nvnc_client_get_address and it
+// should return the sockaddr.
 EXPORT
 const char* nvnc_client_get_hostname(const struct nvnc_client* client) {
 	if (client->hostname[0] == '\0')